Preface

Metabolomics research makes it possible to study changes in metabolism, which may result in the identification of specific metabolites (biomarkers) or metabolic profiles that can be linked to certain states or conditions of organisms. So far, metabolomics studies have effectively shown changes in metabolism resulting from disease or environmental interactions, and provided new mechanistic insights that could not have been identified using classical biochemical approaches. A key aim of using metabolomics is to address fundamental questions in biology and biomedicine, with the ultimate goal to prevent disease and to improve health during the course of the human lifespan.

Metabolomics studies may be considered highly challenging from an analytical chemistry viewpoint; for example, the human metabolome contains more than 100 000 metabolites with different physico-chemical properties in a wide concentration range. Therefore, advanced analytical separation techniques are currently used for the global profiling of metabolites in biological samples. In this context, capillary electrophoresis–mass spectrometry (CE-MS) has emerged as a very useful analytical tool for the analysis of (highly) polar and charged metabolites, as compounds are separated on the basis of their charge-to-size ratio. In comparison to especially chromatographic-based separation techniques, the use of CE-MS in metabolomics and bioanalysis is still underrepresented, despite this approach having some unique analytical characteristics for metabolic profiling studies.

In this book, the possibilities of CE-MS for metabolomics studies are emphasized with a special focus on recent technological developments. Though not explicitly indicated, the book is roughly structured into two parts. After introducing the potential of CE and CE-MS for metabolomics from a historical perspective, the first part deals with chapters on advances in sample preparation, separation conditions, preconcentration techniques, interfacing designs and to some extent data analysis. Then, as a bridge to the second part, the strengths and limitations of CE-MS for metabolomics are discussed in comparison to chromatographic-based separation techniques. The second part highlights applications for which CE-MS is a well-suited approach or may even be considered as key, such as for chiral metabolomics and single-cell metabolomics. Specific attention is also paid to quality assurance and validation strategies, and how to incorporate them in a CE-MS-based analytical workflow to obtain reliable metabolomics data. Within each chapter, the impact of developments in CE-MS methodology and procedures is demonstrated by illustrative metabolomics studies.

Overall, this book should give a contemporary representation of the main technological developments in CE-MS for metabolomics, including important application fields. I hope that the book is useful for both beginners and experts in the field of metabolomics and bioanalysis in general, and that it will stimulate further research in this area. I highly appreciate the efforts of all contributing authors and would like to thank them for their excellent chapters. This book would not have been possible without their valuable contributions. I would also like to thank the referees for their help in the evaluation of these papers and the editorial staff, especially Robin Driscoll, from the Royal Society of Chemistry for their support during the preparation of this book.

Rawi Ramautar

Leiden, The Netherlands